reef
/riːf/ (bre, ipa) · /riːf/ (ame, ipa) · /ˈrēf/ (ame, mw)
reef — noun
- reefsingular
- reefsplural
1. A long, narrow band of rock, coral, or sand that sits just beneath the water's s
A long, narrow band of rock, coral, or sand that sits just beneath the water's surface, creating a serious danger for ships in the area.
The ship's captain warned the crew to stay clear of the coral reef ahead.
coral reef — common collocation
Soraya saw colourful fish swimming near the reef during her first snorkelling trip.
Many ships have been wrecked on the hidden reef off the coast of Australia.
The Great Barrier Reef is one of the largest living structures on Earth.
- open sea
deep water without submerged obstacles
文法句型
a/an + reef
the + reef
adjective + reef
用法筆記
Often used in compound names: 'coral reef', 'barrier reef'. The most famous example is the Great Barrier Reef off the coast of Australia.
常見錯誤
2. A foldable portion of a ship's sail that sailors roll up or tie down to shrink t
A foldable portion of a ship's sail that sailors roll up or tie down to shrink the area exposed to strong wind.
Joaquín tied the reef in the mainsail before the storm arrived.
tie the reef — verb + reef collocation (sailing)
The sailors pulled hard on the ropes to take in a reef.
In heavy winds, a good skipper puts in two reefs to keep the boat steady.
Élise showed the new crew how to tie the reef securely.
文法句型
a/an + reef
take in + a reef
put in + a reef
tie + the + reef
用法筆記
Common in nautical expressions: 'take in a reef' means to reduce sail area; 'shake out a reef' means to release the folded section and expand the sail again. The number of reefs taken is counted: 'one reef', 'two reefs'.
3. Something that blocks progress or causes unexpected difficulty, used like a hidd
Something that blocks progress or causes unexpected difficulty, used like a hidden rock reef that threatens a ship.
The project hit a reef of unexpected costs that delayed the construction.
'a reef of [problems]' — figurative use
Abigail's plan ran into a reef of legal problems she had not predicted.
The negotiations struck a hidden reef when the two sides refused to compromise.
Without proper advice, young businesses often crash into a reef of debt.
- smooth sailing
an idiom meaning easy, uninterrupted progress
文法句型
a reef of + noun (problems, difficulties, issues)
用法筆記
Primarily appears in formal writing and journalism rather than everyday speech. Often paired with verbs like 'hit', 'strike', or 'run into' to maintain the nautical metaphor.
reef — verb
- reefpresent simple I / you / we / they
- reefs3rd person singular
- reefing-ing form
- reefedpast simple
1. To make a sail smaller by rolling, folding, or tying up a part of it, usually be
To make a sail smaller by rolling, folding, or tying up a part of it, usually because the wind has become dangerously strong.
The captain ordered the crew to reef the sails as the wind picked up speed.
reef the sails — the main transitive pattern
Hari learned how to reef the mainsail during his first sailing lesson.
It is safer to reef too early than to wait until the wind becomes unmanageable.
Maeve showed the beginners how to reef by folding the bottom part of the sail.
- shorten sail
a more general nautical phrase for reducing sail area by any method
- shake out
to release a reef and expand the sail to its full size
文法句型
reef + noun phrase (the sail, the mainsail)
be + reefed (passive)
reef + by + V-ing
用法筆記
Frequently used in imperatives and instructional language on sailboats. The amount of reefing is measured in steps called 'reefs' — e.g. 'reef to the first reef point'. The opposite action is 'shake out a reef' (to expand the sail again).